Write a constraint for if a=0 then b=1,if a is not equal to 0 then b should not get randomized

write a constraint for if a=0 then b=1,if a is not equal to 0 then b should not get randomized

In reply to lalithjithan:
See 1800’2012 examples at 18.5.6 Implication and 18.5.7 if–else constraints
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